1. Field of the Invention
The present invention relates to a limited slip differential device that is capable of limiting its differential function by using an electromagnetic solenoid.
2. Description of the Related Art
A limited slip differential device of this kind is disclosed in Japanese utility model laying-open publication No. (Hei) 05-29833. This differential device has differential gears consisting of a planetary gear set, a differential limit mechanism to limit differential function of the differential gears, and a housing containing the differential gears and the limit slip differential mechanism. The differential limit mechanism includes a multi-plate clutch and an electromagnetic clutch mechanism having a magnet plate, an electromagnetic solenoid to attract the magnet plate, and a clutch disposed between the magnet plate and the electromagnet solenoid. In this differential device, the solenoid controls a slip-limit state of the differential gears by changing the amount of coupling force applied to the multi-plate clutch according to the amount of electric current supplied to the solenoid.
The above known conventional limited slip differential device, however, encounters a problem that the differential device keeps the slip-limit state at times due to remanent magnetization in a yoke of the electromagnetic clutch mechanism despite of de-energizing the solenoid.
It is, therefore, an object of the present invention to provide a limited slip differential device which overcomes the foregoing drawbacks and can ensure to disengage a clutch for limiting a differential function of differential gears when an electromagnetic solenoid is de-energized.